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Abdomen:Hollow viscus:Renal pelves and ureters
The ureter is a paired fibromuscular tube that conveys urine from the kidneys in the abdomen to the bladder in the pelvis. The ureter is 25-30cm long and has three parts: # abdominal ureter: from the renal pelvis to the pelvic brim # pelvic ureter: from the pelvic brim to the bladder # intravesical or intramural ureter: within the bladder wall Relations: Abdominal ureter * posteriorly: psoas muscle; genitofemoral nerve; common iliac vessels; tips of L2-L5 transverse processes * anteriorly ** right ureter: descending duodenum (D2); gonadal vessels; right colic vessels; ileocolic vessels ** left ureter: jejunum, gonadal vessels; left colic vessels; loops of jejunum; sigmoid mesentery and colon * medially ** right ureter: IVC, lumbar lymph nodes, Constrictions: the ureter has a diameter of 3mm with three constrictions, which are the most common sites of renal calculus obstruction: * at the pelvi-ureteric junction (PUJ) of the renal pelvis and the ureter * as the ureter enters the pelvis and cross over the common iliac artery bifurcation * at the vesicoureteric junction (VUJ) as the ureter enters the bladder wall Course: * Passes down on medial aspect of the psoas muscle, lying anteriorly to the tips of the L2-L5 transverse processes. * Crosses over the genitofemoral nerve and below gonadal vessels * The right ureter lies behind the D3, and further down, right colic and ileocolic vessels. the left ureter is lateral to IM vessels and cross below the left colic vessels * The ureter leaves the psoas muscle at bifurcation of common iliac artery over SI joint and into the pelvis, courses anteriorly to the internal iliac artery and down the lateral pelvic sidewall. * Male: at the level of the ischial spine it turns forward and medially to enter the posterior wall of the bladder, where it runs an oblique 1-2cm course, before opening into the bladder at the internal ureteric orifice. Crossed by the vas deferens. * Female: runs in the base of the broad ligament and crossed by the uterine artery. Blood supply: multiple sources form longitudinal blood channel along the ureter via blood channels. * Ureteric branch of the renal artery (superior portion) * Branches of abdoiminal aorta, gonadal, common iliac and internal arteries (middle portion) * Inferior and superior vesical and uterine arteries (inferior portion) * Venous drainage is from similarly named veins Lymph drainage: * Abdominal portion of the ureter drains into the para-aortic/caval nodes and pelvic portion into the common iliac and internal iliac nodes Nerve supply: # Sympathetic fibres T10-L1 segments via the coeliac and hypogastic plexuses # Parasympathetic from the pelvic splanchnic nerves # Pain fibres accompany sympathetic nerves similar to the kidneys Variations * Duplication caused by low division of ureteric bud. Upper pole inserts lower into the bladder, vagina, or urethra * Bifid ureter – when duplicated kidneys have separate collecting systems and their ureters unite * Bifid collecting system – one collecting system for duplicated kidneys * Double ureter/multiple ureters – from one kidney and they empty into the bladder separately * Ectopic ureter – empties into an unusual location (lower bladder, urethra, rectum) * Retrocaval ureter – when right ureter passes behind the IVC * Ureterocele * Ureter diverticulum * Twisted ureter course